The primary objective ofthe M.D. Anderson Cancer Center CML-P01 is to improve the treatment of patients with chronic myelogenous leukemia. A fundamental component to meeting this objective is the conduct of focused translational research involving human tissue and blood specimens, allowing investigation of the biology of target and normal tissues, evaluation of treatment effects on both target and normal tissue, and modulation of relevant biomarkers. The CML Cell Bank Core will collect, process and maintain human tissue specimens from patients and will disperse these tissues to CML-P01 investigators. The CML Cell Bank Core has the following objectives: 1. Develop and maintain a repository of intact cells, serum, DNA, RNA and protein derived from blood and bone marrow specimens obtained from patients with CML that are receiving care or evaluation at M.D. Anderson Cancer Center. Samples are collected and processed at the time of diagnosis, during therapy with POI associated clinical protocols, while in remission or at relapse. The core will distribute tissue specimens to CML-P01 investigators for analysis and provide expertise in the interpretation of studies performed on tissue sections within CML-P01 projects The Core will provide comprehensive hematopathologic characterization ofthe samples used in CML-P01 projects. 2. Provide stock and customized Reverse Phase Protein Arrays to CML-P01 researchers. 3. Maintain a comprehensive, prospective interactive database with detailed clinical and pathologic data for patients with leukemia and MDS receiving care or evaluation at M.D. Anderson Cancer Center.